"So, why do they even want to be Catholic?"
IMO, they are under the direct influence of Satan to a degree that would horrify us all if it became visible, and he is using them to attack the Church.
It is not possible for someone to be a practicing gay and a true Catholic. What most don't seem to understand is Catholicism (for the most part) is not a cafeteia religion -- you don't get to pick and choose which parts you will adhere to.
Homosexual relations are a Sin. Promoting them is promoting Sin (which is yet another sin).
This is 0% theological and 100% political.
Yes, they are in fact, infiltrators, satanists at that.
And there's a lot of them, including clergy.